Mode and sensing properties of a silicon-based hybrid plasmonic microring resonator

摘要： A silicon-based hybrid plasmonic microring resonator consisting of a silicon-on-insulator ring which is separated from a silver nanoring by a low-permittivity dielectric is proposed for sensing applications. Benefitting from the hybrid modes and the circular-shaped cross section of nanoring, the hybrid microcavity can attract part of the cavity energy from the silicon ring microcavity, achieving high energy ratio and high refractive index sensitivity. The performance of the hybrid microcavity has been investigated by employing a finite element method and analyzed considering the different structure geometry, showing high quality factor of 1181, small mode volume of 0.154 lm3 and large refractive index sensitivity of 529.6 nm/RIU (refractive index unit). Thus, the presented silicon-based hybrid plasmonic microring resonator provides the potential applications in sensing at deep sub-wavelength scale.